;License:MIT
;(c) 2018-9 by 4am
;
; miscellaneous UI functions
;
; Public functions
; - SoftBell
; - Home
; - BlankHGR
; - BlankDHGR
; - IsSearchKey
; - IsUpDownOrRightArrow
;

;------------------------------------------------------------------------------
; SoftBell
; yell at the user, but, like, gently
;
; in:    none
; out:   C clear
;        Y preserved
;        A=0
;        X=0
;        all flags preserved
;------------------------------------------------------------------------------
SoftBell
         ldx   #32
-        lda   #2
         jsr   @wait
         bit   SPEAKER
         lda   #33
         jsr   @wait
         bit   SPEAKER
         dex
         bne   -
         clc
         rts
@wait ; identical to $FCA8 ROM routine, but ROM is switched out when we need it
         sec
--       pha
-        sbc   #1
         bne   -
         pla
         sbc   #1
         bne   --
         rts

;------------------------------------------------------------------------------
; Home
; clear and display text screen (HARDER THAN IT SOUNDS)
;
; in:    none
; out:   $0106..$011F clobbered
;------------------------------------------------------------------------------
Home
         lda   MachineStatus
         and   #SUPPORTS_SHR
         beq   @noSHR
         lda   NEWVIDEO
         and   #$3F
         sta   NEWVIDEO              ; get out of SHR mode and linear mode
         lda   #$F0
         sta   TBCOLOR               ; white text on black background
         lda   #$00
         sta   CLOCKCTL              ; black border
         sta   CLOCKCTL              ; set twice for VidHD
@noSHR
         ldx   #(@end-@start-1)
-        lda   @start,x
         sta   $106,x
         dex
         bpl   -
         jmp   $106
@start
         ; this will be run from main memory
         +READ_ROM_NO_WRITE
         sta   CLR80VID              ; get out of DHGR mode
         sta   DHIRESOFF             ; get out of DHGR mode
         jsr   ROM_TEXT              ; TEXT
         jsr   ROM_HOME              ; HOME
         +READ_RAM1_WRITE_RAM1
         rts
@end

;------------------------------------------------------------------------------
; BlankDHGR
; clear and show DHGR page 1 without flickering
;
; in:    none
; out:   text page clobbered (but screen holes preserved)
;        $2000..$3FFF/main and /aux cleared
;------------------------------------------------------------------------------
BlankDHGR
         jsr   Home
         jsr   ClearHGR1             ; clear hi-res screen 1
         sta   WRITEAUXMEM
         jsr   ClearHGR1             ; clear hi-res screen 1 in auxmem
         sta   WRITEMAINMEM
         sta   SET80VID
         sta   DHIRESON
         bit   PAGE1
         jmp   HGRMode

;------------------------------------------------------------------------------
; BlankHGR
; clear and show HGR page 1 without flickering
;
; in:    none
; out:   text page clobbered (but screen holes preserved)
;        $2000..$3FFF cleared
;------------------------------------------------------------------------------
BlankHGR
         jsr   Home
         jsr   ClearHGR1             ; clear hi-res screen 1
         bit   PAGE1                 ; show hi-res screen 1 (now blank)
         ; /!\execution falls through here to HGRMode
;------------------------------------------------------------------------------
; HGRMode
; twiddles softswitches to set HGR mode (does not set page 1 or 2)
;
; in:    none
; out:   all registers preserved
;------------------------------------------------------------------------------
HGRMode
         bit   $C057
         bit   $C052
         bit   $C050
         rts

;------------------------------------------------------------------------------
; IsSearchKey
; test whether accumulator contains a key that might trigger a new textrank
; search
;
; in:    A = key
; out:   A &= 0x7F
;        Y preserved
;        X clobbered
;        Z = 1 if this is a search key
;        Z = 0 if this is not a search key
;------------------------------------------------------------------------------
IsSearchKey
         and   #$7F                  ; strip high bit for search characters
         cmp   #$30                  ; control keys and punctuation ignored
         bcc   @badkey
         cmp   #$3A                  ; numbers are good input
         bcc   @goodkey
         cmp   #$41                  ; more punctuation (also ignored)
         bcc   @badkey
         cmp   #$5B                  ; uppercase letters are good input
         bcs   +
         ora   #$20                  ; convert uppercase letters to lowercase
@goodkey
         ldx   #0
         rts

+        cmp   #$61                  ; more punctuation (also ignored)
         bcc   @badkey
         cmp   #$7B                  ; lowercase letters are good input
         bcc   @goodkey
@badkey
         ldx   #1
         rts

IsUpDownOrRightArrow
         cmp   #$8B                  ; up arrow
         beq   @done
         cmp   #$95                  ; right arrow
         beq   @done
         cmp   #$8A                  ; down arrow
@done    rts